1. Field of the Invention
The present invention relates to a digital camera.
2. Description of the Related Art
There are digital cameras as devices for outputting image data for still pictures and moving pictures to a projector or a personal computer and recording such image data in a predetermined recording medium. These digital cameras are formed to include a lens unit having a fixed lens group and a movable lens group, a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor) as a solid state image pick-up device which is disposed in the vicinity of the lens unit, a liquid crystal display device and integrated circuits such as ASICs (Application Specific Integrated Circuits).
In these digital cameras, since, the solid state image pick-up device and the integrated circuits are heated to high temperatures, it is necessary to cool these components so that their temperatures are suppressed to their so-called operation ensuring temperatures or lower, and there have been made various proposals in relation to devices for cooling these solid state image pick-up device and the integrated circuits which are heated to higher temperatures.
For example, Japanese Unexamined Patent Publication No. 2006-91399 proposes a cooling method in which a vent hole is formed on a lens unit in a position lying in the vicinity of the camera housing, a heat conductive member (a heat pipe) is disposed on a back side of the solid state image pick-up device, and an end portion of the heat conductive member is extended to the vent hole on the lens unit, so that the solid state image pick-up device is cooled by cooling the heat conductive member.
In these days, digital cameras become smaller in size and thinner in thickness, and since various devices such as a solid state image pick-up device and an integrated circuit, various types of substrates, a battery and a liquid crystal display device are accommodated in a small and thin camera housing, there has been caused a problem that it is difficult to ensure a sufficient space for cooling the solid state image pick-up device and the integrated circuits.
In addition, although there has been adopted a method in which heat, of the solid state image pick-up device and the integrated circuits is released to a heat conductive member made of a metal material or the like, so that the solid state image pick-up device and the integrated circuits are cooled by cooling the metal material, since the digital camera is small and thin, there has been caused a problem that heat of the heat conductive member is conducted to the camera housing (an outer casing) and is then conducted to the hands of the photographer.
Then, there may be a case where the camera housing is formed of a material other than metals which has a low thermal conductivity. As this occurs, however, the rigidity of the camera is reduced, leading to a problem that the impact resistance is reduced.